Study Details Toxic Elements Found in Stranded Whales and Dolphins
搁浅的鲸鱼. (Stranding response conducted under a stranding agreement between NOAA Fisheries Service and 能力 海洋研究所港湾分所 under the authority of the MMPA).
Whales and dolphins get their nutrients and essential elements through their diet. 吃鱼的时候, 鱿鱼, 章鱼, 甲壳类动物和其他海洋哺乳动物, they are also exposed to heavy metal contaminants.
Elevated levels of toxins have been found in stranded dolphins and whales along the Southeastern Coast of the United States. Monitoring toxic contaminants in these stranded marine animals, which serve as important sentinels of env铁mental contamination, 它们的健康可能与人类健康有关, 是至关重要的.
然而,, data remain sparse on how specific elements are distributed within an animal’s body, especially for many rarely encountered species, 以及毒性水平与性别的关系, 品种, 年龄和其他人口因素.
一项由 KU体育官网APP’s 海洋研究所港湾分所 与一组科学家合作, 评估患病率, concentration and tissue distribution of essential and non-essential trace elements, including heavy metal toxicants in tissue (blubber, 肾脏, 肝, 骨骼肌, skin) and fecal samples collected from 90 whales and dolphins stranded in Georgia and Florida from 2007 to 2021.
研究ers analyzed 319 samples from nine species for concentrations of seven essential (钴, 铜, 铁, 锰, 钼, 硒, 锌)和五种非必需元素(砷), 镉, 引领, 汞, 元素分析物. Species in the study all occupied high and similar trophic levels and consumed a mixture of cephalopods and fishes.
该研究结果发表在该杂志上 细胞出版社:氦 表明里索海豚(大铁钳将)和短鳍领航鲸(Globicephala macrorhynchus) had the highest median concentrations of 汞, 镉 and 引领, while dwarf sperm whales (Kogia硅镁层)的比例最低.
Adult pygmy and dwarf sperm whales that stranded during 2019 to 2021 had higher concentrations of arsenic, 铜, 铁, 引领, 锰, 硒, 铊 and zinc compared to those that stranded during 2010 to 2018, suggesting an increasing risk of exposure over time.
“When we separated phylogenetic groups into 年龄阶层es and compared median concentrations of heavy metals in specific tissue types between adult specimens of species, 我们发现了一些有趣的趋势,” 安妮页面, D.V.M., Ph.D., senior author, an associate 研究 professor and clinical veterinarian, 能力 港分公司.
The highest concentrations of many elements (e.g., 镉, 钴, 铜, 锰, 钼, 铊, 锌)存在于粪便样本中, illustrating the usefulness of this non-invasively collected sample.
除了粪便样本, hepatic or 肝 tissues had the highest concentrations of 铁, 锰, 汞, 钼 and 硒 in most species; renal or 肾脏 tissues had the highest concentrations of 镉; skin had the highest concentrations of zinc; and 铜, arsenic and 引领 concentrations were primarily distributed among the 肝 and 肾脏s.
The lowest median concentrations of 汞 and 镉 were in 肝, 肾脏, 脂肪和肌肉样本, with the lowest skin 汞 concentration and the lowest 肝 引领 concentration all from dwarf sperm whales.
Mercury is one of the most toxic elements in marine systems and can bioaccumulate and biomagnify through marine food webs. Cetaceans are exposed to 汞 and other toxic metals mostly by consuming contaminated prey items, 哪些会在肝脏中积聚汞, 肌肉和其他组织随着时间的推移.
“Exposure to heavy metal contaminants can result in oxidative stress, 哪些会损害蛋白质功能, 破坏DNA并破坏膜脂,佩奇说。. “Heavy metal exposure has been linked to degenerative heart disease, immunodeficiency and increased parasite infestations, 其他疾病风险.”
Findings from the study provide important baseline data needed to further assess the pathophysiological mechanisms and ecotoxicological hazards associated with exposure to and accumulation of trace elements in tissues of free-ranging whales and dolphins.
“Because tissue concentrations of heavy metal contaminants also vary based on an individual animal’s sex, 年龄阶层, 营养水平和位置, 除其他因素外, it is important to first establish baseline values and then continue to monitor cetacean populations for exposure to these toxicants,佩奇说。.
Species examined in the study were pygmy sperm whales (Kogia breviceps); dwarf sperm whales; Gervais’ beaked whales (Mesoplodon europaeus); Risso’s dolphins; short-finned pilot whales; sperm whales (-勒瓦); melon-headed whales (Peponocephala依勒克拉); a Blainville’s beaked whale (Mesoplodon densirostris); and a false killer whale (Pseudorca crassidens).
Study co-authors represent 能力 港分公司; the U.S. Coast Guard Academy; University of Alabama at Birmingham; Hubbs-Sea World 研究 Institute; Blue World 研究 Institute; Florida Fish & 野生动物保护委员会，鱼类 & Wildlife 研究 Institute; and the Georgia Department of Natural 资源.
This work was supported by the Florida State License Plate Program “Protect Wild Dolphins” and “Protect Florida Whales” grants (administered by the 海洋研究所港湾分所 Foundation); the Link Foundation; the John H. Prescott Marine Mammal Rescue Assistance Grant; SeaWorld Busch Gardens Conservation Fund; Discover Florida Ocean’s License Plate; and the Brevard County Tourism and Development Council.
能力,